1. Field of the Invention
The present invention is an electric junction box suited to be mounted to an engine room for a vehicle.
2. Description of the Related Art
A wide variety of electronic devices are mounted to a vehicle. In order to supply electrical energy to such an electronic device, an electric junction box that includes an electrical component such as a fuse and a relay, and is disposed between an electronic power source and the afore-mentioned electronic device has been proposed.
The electric junction box may be also called as a “junction block”, a “fuse block”, or a “relay block”. These terms can be interchangeably used herein.
FIG. 5 shows a cross-sectional view of a conventional electric junction box.
The junction box 100 is shown to include a case body 101 formed of synthetic resin. For more detail, see Japanese publication of patent application No. H11-252747. The case body 101 includes a receiving portion 102 capable of receiving a joint 105 having a cap 104 covering terminal portions 103a of electrical conduits 103, as well as a portion 106 for mounting an electronic part thereto. In the area of the joint 105, a plurality of electrical conduits 103 is connected to each other.
The cap 104 is bag-shaped, and is formed of material which has a tendency to contract when heat is applied, thereto. The cap 104 is configured to protect the terminal portion 103a of the electrical conduit 103 from liquid such as water, and any damage. In practice, a plurality of terminals 103 is also protected due to the cap 104 from being separated from each other.
The receiving portion 102 has a recess. In particular, the receiving portion 102 is made tubular having a wall in its one end portion. The receiving portion 102 has a diameter enough to hold the joint 105 therein. The joint 105 is press-fitted into the receiving portion 102 through an opening disposed in the receiving portion 102.
However, there are several drawbacks and problems in the afore-mentioned conventional electric junction box 100. In detail, once the cap 104 is subject to heat, it is contracted. In this situation, the outer diameter of the afore-mentioned joint 105 generally varies within a wide range. For example, in a case where the outer diameter of the joint 105 is made extremely small or narrow, a clearance or gap is caused between the joint 105 (i.e., the outer surface of the joint 105) and the inner face of the receiving portion 102. In this situation, the joint 105 is not allowed to be securely inserted into the receiving 102, as well as, to be well press-fitted into the receiving portion 102. In addition, the joint 105 should be fixed to the receiving portion 102 by means of an adhesive tape, a pressure sensitive tape or sheet, and so on. Accordingly, required parts and efforts are correspondingly increased.